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C20XE Engine Problems....
rallyingden - 7/7/08 at 09:43 PM

The saga continues......

I have searched the forum back to 12 months ago and cannot see a topic covering our problem so I hope there is some help / ideas out there coz we are scratching our heads having tried everything we can think of.

My lad has just fitted a 2ltr XE redtop and we have had problems in getting it running. The engine ran fine in the doner car and we fitted the doner's ECU and wiring loom.

We have changed the fuel pump, ICV and the pressure regulator and as it stands the symptoms are....

Note we have seperate control over the fuel pump.

Engine starts with fuel pump off but races at quite high rev's .
Turn the fuel pump on and the rev's die to a stall.
If you "play" with turning the fuel pump on/off you can get the engine to come down to a more normal tick over rate running with pump on but you cannot rev it unless you do it very very gently.
If the engine stops you have to turn the pump off, crank it over on full throttle then lift off and the car will fire. the exhaust is pointing to the ground (temp) and the floor is covered with black soot as are the plugs but they are NOT wet.
Sometimes the engine sounds as if its missfiring, down to 3 or even 2 but you can coax it back to all 4.

Any ideas will be very much appreciated as this is becomming a real pain not to mention I want my garage back

Cheers RD


Mark G - 7/7/08 at 09:46 PM

sounds like you're flooding it to me.

are you running a fuel pressure regulator?


perksy - 7/7/08 at 10:00 PM

Would be worth getting a Fuel pressure gauge on it and seeing exactly what pressure it's running at
also check the wiring and setting of the TPS

If it's run like this for a while, change the Plugs because they'll be past their best by now...


Jackman - 7/7/08 at 10:01 PM

Assuming you still have the engines full mangement system on there have conected up the coolant temp sensor ? If this is reading very low or open circuit the ecu will give the engine more fuel .IT will think the engine is cold.


rallyingden - 7/7/08 at 10:04 PM

Using standard fule regulator on Injection rail.
Brand new plugs.

I am waiting for a couple of gauges to check pressure but we tried fitting a secon (manual) regulator in the feed to the injection rail to try and limit the pressure it was being fed at.
We are using a 2.5bar pump.

RD


rallyingden - 7/7/08 at 10:07 PM

Jackman
We have checked this is connected, cannot vouch for its condition but the engine IS cold anyway.

RD


Jackman - 7/7/08 at 10:22 PM

If you have access to some from of code reader it mite also be worth seeing if it has eny stored trouble codes in the ecu.Aswell as a fuel presure check.


MkIndy7 - 7/7/08 at 10:54 PM

Is the fuel pump running the right way? +ve and -ve wireing and also flow direction.

From that description it sounds like it runs better after having the pump running for a while and then stopping it running.

How about turning the fuel off completely and trying to run it on an aerosol, that might highlight fuel or ignition.

Is it coil pack or Dizzy ignition?
The Distributor cap and Rotor cap on mine was quite unexpectedly shot when I got it


Werner Van Loock - 8/7/08 at 06:39 AM

If the pump is running and engine not, is there anything coming back from the return line into the fuel tank?

2.5bar pump? are you sure, seems low for injection. Most pumps produce near 5 bar, but are relieved by the pressure regulater to 3 bar. So most problems arise there if the pressure regulator is shot, then you get 5 bar on your rail instead of 3. this could also explain why it runs better without the pump running as the pressure is relieved by the injectors opening and if you fiddle with the on-off of the pump it will keep the pressure near what is needed.

Isn't your return line blocked? (there is a return line right?)


rallyingden - 8/7/08 at 05:05 PM

I have been told its a 2.5 bar pump!
I will fit a pressure gauge and see what we have.

Return line clear as far as connection to tank ( ran into a petrol can )

Thanks
RD


Stu16v - 8/7/08 at 09:12 PM

Hmm. A few things to try/report back on...

1. Disconnect the air-flow meter and try running it again. It will run without the meter, in 'limp home' mode. If it suddenly sounds a lot better the AFM is the culprit (don't take much of a knock to cabbage an AFM). However, it might be the same...

2. If the above hasn't found the problem, firstly run the engine without the pump till it dies. Then pull the injectors with the fuel rail out of the manifold complete, and stick them in suitable (preferably clear) containers. With the ignition switched on, get an assistant to power the fuel pump up, and see if any (or all) of the injectors are 'injecting'. Without the engine turning, they shouldn't be. If that is OK, do the same, but the the engine turning over on the starter. The injectors should 'pulse' fuel now...

3. If it is an older XE loom (it might be the same on later ones too), there will be two wires by the ECU plug. One will be brown and yellow, the other brown and white. Assuming you have wired up the Engine Management light up, joining these two wires together will make the ECU give out any fault codes when the ignition is switched on. Fault codes are given by 'X' flashes, followed by a pause, follewed by 'Y' flashes. The number 'X' and 'Y' will give you a 2 figure number that can be translated into a fault code. The codes themselves are freely available on the net - but Migweb would be a good place to start...


rallyingden - 9/7/08 at 07:05 PM

quote:
Originally posted by Stu16v
Hmm. A few things to try/report back on...

1. Disconnect the air-flow meter and try running it again. It will run without the meter, in 'limp home' mode. If it suddenly sounds a lot better the AFM is the culprit (don't take much of a knock to cabbage an AFM). However, it might be the same...

2. If the above hasn't found the problem, firstly run the engine without the pump till it dies. Then pull the injectors with the fuel rail out of the manifold complete, and stick them in suitable (preferably clear) containers. With the ignition switched on, get an assistant to power the fuel pump up, and see if any (or all) of the injectors are 'injecting'. Without the engine turning, they shouldn't be. If that is OK, do the same, but the the engine turning over on the starter. The injectors should 'pulse' fuel now...

3. If it is an older XE loom (it might be the same on later ones too), there will be two wires by the ECU plug. One will be brown and yellow, the other brown and white. Assuming you have wired up the Engine Management light up, joining these two wires together will make the ECU give out any fault codes when the ignition is switched on. Fault codes are given by 'X' flashes, followed by a pause, follewed by 'Y' flashes. The number 'X' and 'Y' will give you a 2 figure number that can be translated into a fault code. The codes themselves are freely available on the net - but Migweb would be a good place to start...



Thanks.

Connected pressure gauges up to feed and return lines. Feed 2.5bar Return 0.1bar connected to tank. Rises to 2+bar with thumb over end.
Sucked on vac pipe to regulator, I could get inlet pressure to drop to 2 bar.
All in all I think pressures are OK and reg is working.


Answers
1. Ran without AFM ... No difference.

2. Removed injector rail no passing when pump on. Pulsing when engine cranked over, they do seem to pulse quite a bit. after two sessions of about 15 seconds the standard plastic cups were nearly 1cm full of fuel........ Is this too much ? Why?

3. Will get any fault codes as soon as I can. Not done this yet.

To me it seems to be injecting rather a lot of fuel but I'm not sure whats normal.

Thanks for the help so far ..... keep it coming.

Cheers RD


Stu16v - 9/7/08 at 10:14 PM

2. Hard to say if it is too much fuel, as I don't know what size cups you used!
But if they are 'pulsing', and the fuel pressure is fine, the fuel is at leat being 'regulated'. The problem would seem to point to ECU, or messages getting to the ECU.

A bit stumped myself at this point. Drag the codes out (if any), in the meantime, I'll have another think...


MkIndy7 - 10/7/08 at 12:01 AM

Well thinking back if it ran fine in the Donor.. whats changed since then?

How long was it stood?

Is the fuel pump, tank, breather and filters exactly the same or of a similar setup/spec?

Is the wireing correct?
For fuel pumps and pressures etc AFAIK the Fuel pump should run when the ignition comes on and then switch off, (for some reason mine runs constantly but that may be a back feed from somwhere else.)

My XE engine had probably been stood for about a year, the fuel was a horrible brown colour but it still started ok after i'd repaired the Crank Position Plug it fired up no problem.


rallyingden - 13/7/08 at 12:11 PM

quote:
Originally posted by Jackman
Assuming you still have the engines full mangement system on there have conected up the coolant temp sensor ? If this is reading very low or open circuit the ecu will give the engine more fuel .IT will think the engine is cold.


Jackman

You were correct It was the coolant sensor. Just put new one in and hey presto fires up & runs great........ Thanks

RD